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All right, let's take on

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the lateral plantar nerve.

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This is scary.

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Let's start easy.

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We've got our friends Tom, Dick, and Harry.

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Tom, Dick, and Harry.

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And then the vascular and the

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nerve bundle, the tibial nerve.

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Now let's follow the tibial nerve high.

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There it is.

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Now let's follow it low.

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The tibial nerve is going to

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bifurcate into two nerves.

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The one in the front is the medial plantar nerve,

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and we're interested this time in the lateral

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plantar nerve, which sits the lateral plantar

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right next to the posterior tibial artery in

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what's called the talocalcaneal canal region.

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And then it's gonna course medially between

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the medial and lateral plantar arteries.

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So let's look at this artery

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and watch it separate.

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There it is.

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This artery's splitting into two right here.

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Split into two and there is the lateral

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plantar nerve directly adjacent to that split.

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Sorry, here's one part of the artery.

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Here's the other part of the artery.

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One, two, there's the nerve right next to it.

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Let's keep going down now and follow the

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course of the lateral plantar artery.

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See, it's headed laterally.

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Well, that makes total sense.

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Now, right at this location, like the

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medial plantar nerve, it's seen between the

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abductor hallucis and the quadratus plantae.

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That's fine.

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And now let's continue following it.

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Here it is right here, between the tibial

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arteries, that's the nerve right in between,

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and now we have the flexor digitorum brevis.

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So now it's sitting between the flexor

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digitorum brevis and the abductor hallucis.

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Let's keep following it.

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As you might expect, it should be

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heading laterally, that's why it's

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called the lateral plantar nerve.

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Let's see if we can keep following it.

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There it is.

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I've got my arrow right on it.

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Stare at it for one second.

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Now let's keep following it.

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Keep following it.

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It's headed laterally.

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There it is.

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Oh my, we still see it.

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We still see it buried in this muscle.

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We perhaps still see it right here

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as an area of subtle linearity.

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We still see it headed off to the side.

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And perhaps we see it right here.

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That may be part of it right there.

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And we are right next to

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the abductor digiti minimi.

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So we're between the abductor digiti minimi

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and the flexor digitorum brevis, and this most

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likely is the best candidate for the lateral

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plantar nerve, which is now going to divide

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into two terminal branches, which are a little

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small for us, the superficial and deep branches.

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The superficial branch divides into a proper

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digital branch and a common digital branch.

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Now on MRI, let's look at our medial and

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lateral plantar nerve, but in the coronal

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projection, using a fat-suppressed, water-

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water-emphasized image, just to show you how

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these two nerves compartmentalize from

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proximal to distal, or high and low.

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So if I put a cursor on my medial plantar

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nerve, you can see on the right where it

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is relative to the coronal projection.

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I'm even going to draw on it for emphasis.

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So here is my medial plantar nerve and right

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below it, I should put another color on it.

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Just again, for emphasis, let's go with orange.

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Right there is my lateral plantar nerve.

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Now let's scroll.

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I'm going to make it even bigger just to

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really kind of put it right in your face.

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There's the medial plantar nerve.

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You can even see the little bundles of

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it and there's the lateral plantar nerve.

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Now, that goes back.

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Now let's go forward.

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And they're separating.

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Medial plantar nerve, lateral

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plantar nerve below it.

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Medial, lateral.

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Medial, lateral.

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And now the lateral, which, which was

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initially between just the abductor, in the

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quadratus plantae, now it's starting to assume

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a position right underneath and alongside,

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snuggling next to the flexor digitorum brevis.

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Now we start to lose it, but it's still in

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there, and this is where it starts to give

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off its calcaneal branches, and it's going

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to head over to the other side, towards

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the abductor digiti minimi, and it's these

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calcaneal branches that are given off.

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That will produce Baxter's neuropathy.

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Again, if we go backwards a little bit, you

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can see that the medial plantar nerve is always

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going to sit a little bit higher than the

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lateral plantar nerve, even as we scroll down.

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Medial, lateral, medial, lateral.

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I think that really shows it optimally.